1. Field of the Invention
The present invention generally relates to scroll compressors for refrigeration units. More specifically, the present invention relates to a system, method, and apparatus to minimize the amount of debris contacting the sides of a moveable scroll in a scroll compressor.
2. Discussion of the Related Art
Scroll compressors are well known in the art. Scroll compressors are used in refrigeration systems to compress coolant as part of a cooling process. A typical scroll compressor is comprised of two scrolls. FIG. 1 illustrates a typical scroll compressor 100 utilized in the prior art. The first scroll is a stationary scroll 105 and is physically mounted to a base. A moveable scroll 110 moves in a path between the walls of the stationary scroll 105. As the moveable scroll 110 moves, it tightly contacts the stationary scroll at numerous locations, trapping gas coolant in pockets between the locations at which the moveable scroll 110 contacts the stationary scroll. As the moveable scroll 110 moves in the path between the walls of the stationary scroll 105, the contact points move, pushing the coolant gas trapped between the contact points progressively closer to the center of the scroll compressor 100. As the coolant moves closer to the center, it becomes more compressed, since the pockets continually shrink. As the coolant becomes more and more compressed, its temperature increases. As the compressed coolant gas reaches the center, the pressure becomes so great that the coolant typically liquefies. Once the coolant reaches the center, it is pumped into coils of a cooling system.
The liquid coolant then flows through the coils, where it dissipates heat. After the high pressure liquid coolant has completely flowed through the coils, it reaches an expansion valve, through which it may flow. The expansion valve is similar to a small hole. On one side of the expansion valve is the high pressure liquid coolant, and on the other side is a low pressure area. Once in the low pressure area, the liquid coolant immediately boils and its temperature drops substantially, to a temperature suitable for cooling. The chilled coolant gas may then flow through pipes in the low pressure area until it again reaches the scroll compressor 100, and the process may repeat itself
Typical scroll compressors 100 utilize moveable scrolls 110 and stationary scrolls 105 formed of the same material, or of similar materials having similar hardness. However, using materials of the same or similar hardness can be problematic. For example, if debris falls into the scroll compressor 100, into a space between the moveable scroll 110 and the stationary scroll 105, the debris can damage the scroll compressor 100.
FIG. 2 illustrates a sectional view of a typical moveable scroll 110 in the prior art. The moveable scroll 110 typically has a flat top and a flat bottom. Such a design results in a relatively short lifetime because if debris falls into the scroll compressor 100, it may damage either the moveable scroll 110 or the stationary scroll 105 as it falls down into the space between the scrolls and down to the bottom of the scroll compressor 100. Debris with sharp edges that become trapped on the flat surface on the top of bottom of the moveable scroll may cut through the stationary scroll 105 or the moveable scroll 110 and cause leakage. Also, if debris falls on top of the moving scroll, the debris will typically fall off the top and down into the scroll compressor, causing damage and shortening the scroll compressor""s usable lifetime.
Also, some moveable scrolls in the art also do not form a tight seal between the top and bottom of the moving scroll and the stationary scroll. This can result in leakage of coolant from the scroll compressor 100.
Accordingly, the scroll compressors 100 in the prior art are all relatively inefficient because they allow too much debris to fall down into the space between the moving scroll and the stationary scroll. As a result, scroll compressors in the art have relatively short useful lifetimes.